Inside pipe cutter



Dec. 23, 1952 R. A. RANSOM y INSIDE PIPE CUTTER Filed oct. s. 194s I In?M da m H .JSS 3415'4uw42cow. Vfk/ Q /vl/ .9 fm 7 @3 @2:22:22:222:57j

Dec. 23, 1952 R. A. RANSOM INSIDE PIPE CUTTER 2 SHEIEFPS-SHEETll 2 FiledOCT.. 8, 1948 .IIIIIIIIII Il l llllllnll m w m w.

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Patented Dec. 23, 1952 UNITED STATES PATENT OFFICE INSIDE PIPE CUTTERRussell A. Ransom, Houston, Tex.

Application October 8, 1948, Serial No. 53,476

Claims. 1

This invention relates to an inside pipe cutter.

An object of the invention is to provide a tool of the characterdescribed which may be lowered into the pipe, or casing, in a well bore,by means of a flexible line, such as a cable with means for anchoringthe tool at a selected place where the cut is to be made, said toolhaving novel means for rotating and expanding the cutters to sever thewell pipe or casing.

It is another object of the invention to provide a cutter of thecharacter described which embodies a weight and novel means associatedtherewith and to be rotated thereby to rotate the cutter carrier andcutters with novel means associated therewith for at the same timeexpanding the cutters.

The invention also embodies means for releasing the tool from the wellpipe upon completion of the cut to allow the tool to be withdrawn fromthe well.

Other objects and advantages will be apparent from the followingspecication which is illustrated by the accompanying drawings, where-1n:

Figure 1 is a vertical, sectional view of the lower end of the toolshowing the tool in cutting position.

Figure 2 is a Vertical, sectional View of the upper end thereof.

Figure 3 is a Vertical, sectional View of the upper end of the toolshowing the weight being lowered to active position.

Figure 4 is a cross-sectional View taken on the line 4--4 of Figure 1.

Figure 5 is a vertical, sectional View of the lower end of the tool ininactive position while being lowered into the well.

Figure 6 is a vertical, sectional view of the upper end thereof.

Figure 7 is a cross-sectional view taken on the line I-'I of Figure 6,and

Figure 8 is a cross-sectional View taken on the line 8-8 of Figure 6.

Referring now more particularly to the drawings wherein like numerals ofreference designate the same parts in each of the figures, the numeral Idesignates the cutter body onto whose lower end there is screwed theguide 2 whose lower end is downwardly tapered.

The upper end of the cutter body is reduced in diameter and iscylindrical in shape.

Pivotally mounted in this cutter body there are the arcuate cutters 3which are pivoted at corresponding ends in the body and whose other endsare free and terminate in outwardly directed bits 4. These cutters workin an external annular groove 5 in the cutter body and are normally heldretracted inwardly by means of springs 6.

The body is provided with external longitudinal grooves 'l wherein thecutter expanders 8 are mounted. These expanders work against the innersides of the cutters, as indicated in Figures 1, 4 and 5, and theirlower ends are gradually widened, or wedge shaped, so that as theexpanders move upwardly the cutters will be gradually expanded. Theupper ends of these expanders are pivotally connected to a supportingsleeve 9 around the reduced upper end of the body and the upper end ofsleeve 9 is provided with an external annular flange I0.

Fitted onto the lower end of the reduced upper end of the body I thereis a cylindrical shield I I which is provided with vertical slots I2 inregistration grooves I and in which the expanders 8 work. The upper endof this shield is internally enlarged in diameter and internallythreaded and screwed into said internally threaded upper end there istubular anchor I3 whose lower end has a swivelling connection with thesupporting sleeve 9. The reduced upper end of the cutter body extendsaxially through this tubular anchor I3.

The upper end of the cutter body works through a ring I4 which isscrewed into the upper end of the shield I I.

Above the shield II and resting on it there is a jaw expander I5 havingthe downwardly and outwardly tapering faces I'I on which the casingengaging jaws I8 are slidably mounted and with which they have adovetailed connecticn. The outer sides of the jaws I8 are toothed toengage the pipe to be cut.

The upper end of the jaw expander is reduced in diameter and extendedupwardly forming a tubular guide I9 on which an annular anchor 20 isslidably mounted and this anchor is connected to the jaws beneath bymeans of suitable links, as 2|.

The upper end of the body I has a reduced upwardly extended stem 22which extends up axially into the expander I5 and a driving shaft 23 isprovided whose lower end is extended axially through the guide I9 and isconnected, by means of left hand threads 24 to the upper end of saidstem 22.

The upper end of the shaft 23 is enlarged and is provided with deepspiralled grooves 25 in the external surface thereof and secured to theupper end of the shaft 23 there is an enlarged cylindrical head 26.

There is a tubular weight 2I whose lower end is tubular in form andwhose upper end is formed into a head 28 which is secured in place inany preferred manner and to which the lower end of the operating cable29 is secured. This cable extends to the ground surface and is providedto lower and withdraw the tool.

The lower end of the weight 21 is reduced, internally, in diameterforming an internal annular shoulder 3E] and the head 26 ts closelywithin said weight 21 above the shoulder 30.

The lower end of the weight 21 is provided with radial slots 3I, 3!whose inner ends are widened upwardly and mounted in these slots thereare the actuating dogs 32, 32 which are normally held in horizontalposition by means of the coil springs 33, 33 which operate thereagainstso as to hold the free ends thereof extending radially inwardly.

The jaw expander I is provided with vertical bearings 5G in which therelease rods 35 are slidably mounted. The lower ends of these rods,beneath said expander, are reduced in diameter thus forming the externalannular downwardly facing shoulders on said rods 35. The reduced lowerends of the rods 35 extend through bearings in the ring I4 and extend ondown into aligned bores 31 in the tubular anchor I3.

In operation the tool is assembled, as shown in Figures 5 and 6, and islowered into the well casing to be cut. When the point is reached atwhich the cut is to be made an upward pull may be taken on the cable 29thus elevating the expander I5 into contact with the jaws I8 and thuswedging the jaws out securely against the casing. The cable 29 may thenbe slacked off and the weight 21 will move downwardly as is indicated inFigure 3 but the jaw expander I5 is wedged tightly in place and will notmove downwardly.

Screwed onto the upper end of the guide I9, with left hand threads,there is a tubular housing 31 through which the shaft 23 works and whichis provided with an external annular shoulder 38 at its lower end. Thehousing has the vertical side slots 31a, 31a through which the dogs 32work. lThe upper end of this housing extends into the weight 21.

When the weight 21 reaches the limit of its downward movement it willland on said shoulder 33 and its downward movement will be stopped.

An upward pull may then be taken on the cable 29 and the dogs 32 willengage in the grooves 25 and upon further upward pull the driving shaft23 will be thereby rotated thus rotating the cutter body I and thecutters. As the cutter body I is rotated the anchor I3, which is heldagainst rotation by the rods 35 will be gradually moved upwardly thuselevating the expanders 8 and forcing the cutters outwardly.

The tubular anchor I3 is moved upwardly by the rotation of the shield IIand this shield is rotated by the rotation of the expanders 8 which workin the radial slots I2 of the shield. The operation of lowering theweight 21 and elevating it may be repeated until the cut through thecasing is completed.

The rotation of the shield II will also unscrew the ring Ill from saidshield allowing said ring I@ to move upwardly against the shoulders 56of release rods 35 under the influence of the coil spring 35.

When the cut has been completed the expanders 8 will have passed abovethe cutters 3 and 4 said cutters will then be retracted by the springs6.

The head 31 and guide I9 and expander I5 may then be jarred slightlydownwardly to release the jaws I8 and said jaws will be held upwardly ininactive position by the rods 35 which will then be held in elevatedposition by the ring I4 and spring 39 and the tool may then be wthdrawnfrom the well.

If for any reason it should be decided to withdraw the cutter from thewell pipe or casing before said pipe or casing has been completelysevered, as is shown in Figure 1, but after the ring I4 has beenunscrewed from the upper end of the shield I I the head 31 and guide I9and expander I5 may be jarred downwardly to release the jaws I8 and anupward pull then taken on the cable 29 which will shear off the bits 4and allow the cutter to be withdrawn.

A preferred form of the pipe cutter, hereinafter claimed, has beenspecifically shown and described by way of illustration merely while thebroad principle of the invention will be defined by the appended claims.

What I claim is:

l. An inside pipe cutter comprising, a cutter body having an externallongitudinal groove, a cutter pivoted on the bodywhose outer end ismovable outwardly into cutting relation with the pipe, means normallyholding the cutter retracted, a cutter expander in the groove inwardlyof the cutter, an anchor above the expander, means having a swivellingconnection with the anchor and to which the upper end of the expander isconnected, a shield around the body in which the anchor is threaded andhaving a slot in which the expander works whereby upon rotation of thebody the shield will be rotated to elevate the anchor and expander tomove the cutter outwardly, means above the shield including a pipeengaging jaw engageable with the pipe to be cut to hold the cutter bodyagainst upward movement, a drive shaft connected to the upper end of thebody, weight means operable from the ground surface and operativelyconnected with the shaft to rotate said shaft and body and means formaintaining the anchor against such rotation.

2. An inside pipe cutter comprising, a cutter body having an externallongitudinal groove, a cutter pivoted on the body whose outer end ismovable outwardly into cutting relation with the pipe, means normallyholding the cutter retracted, a cutter expander in the groove inwardlyof the cutter, an anchor above the expander, means having a swivellingconnection with the anchor and to which the upper end of the expander isconnected, a shield around the body into which the anchor is threadedsaid shield having a slot in which the expander works whereby uponrotation of the body the shield will be rotated to move the anchor andexpander to actuate the cutter outwardly, means above the shieldengageable with the pipe to be cut to hold the cutter body againstupward movement, a drive shaft connected to the upper end of the body,weight means operable from the ground surface and operatively connectedwith the shaft to rotate the shaft and body and means for maintainingthe anchor against such rotation.

3. An inside pipe cutter comprising, a cutter body having an externallongitudinal groove, a cutter pivoted on the body whose outer end ismovable outwardly into cutting relation with the pipe, means normallyholding the cutter retracted, a cutter expander in the groove inwardlyof the cutter, an anchor above the expander, means having a swivellingconnection with the anchor and to which the expander is connected, ashield around the body in which the anchor is threaded, said shieldhaving a slot in which the expander works whereby upon rotation of thebody the shield will be rotated to cause upward movement of the anchorand expander to thereby move the cutter outwardly, anchoring means abovethe shield engageable with, and releasable from, the pipe to be cut, adriving shaft connected to the upper end of the body, Weight meansoperable from the ground surface and engageable with the shaft `torotate the shaft and body, a release ring threaded into the upper end ofthe shield, a release rod extending through the anchoring means andrelease ring and into the anchor to hold the anchor and release ringagainst rotation with the body.

4. An inside pipe cutter comprising, a cutter body, a cutter pivoted onthe body whose outer end is movable outwardly into cutting relation withthe pipe, means normally holding the cutter retracted, a cutter expanderin the body inwardly of the cutter, an anchor above the expander, meanshaving a swivelling connection with the anchor and to which the upperend of the expander is connected, a shield around the body into whichthe anchor is threaded, said expander interlocking the body and shieldfor simultaneous rotation whereby upon rotation of the body the shieldwill be rotated to move the anchor and expander to actuate the cutterouwardly, anchoring means above the shield engageable with the pipe tobe out to hold the cutter body against upward movement, a drive shaftconnected to the upper end of the body, weight means operable from theground surface and operatively connected with the shaft to rotate saidshaft and body, means for maintaining the anchor against such rotation.

5. An inside pipe cutter comprising, a cutter body, a cutter pvoted onthe body whose outer end is movable outwardly into cutting relation withthe pipe, means normally holding the cutter retracted, a cutter expanderin the body inwardly of the cutter, an anchor above the expander, meanshaving a swivelling connection with the anchor and to which the upperend of the expander is connected, a shield around the body into whichthe anchor is threadedy a release ring threaded into the shield abovethe anchor, said expander interlocking the body and shield forsimultaneous rotation whereby upon rctation of the body the shield willbe rotated to move the anchor and expander to actuate the cutteroutwardly and to unscrew the release ring, anchoring means above theshield engageable with the pipe to be cut to hold the cutter bodyagainst upward movement, a drive shaft connected to the upper end of thebody, Weight means operable from the ground surface and operativelyconnected with the shaft to rotate said shaft and body and means formaintainingr the anchor against such rotation, a release rod extendingthrough the anchoring means and release ring and into the anchor to holdthe anchor and release ring against rotation with the body,interengaging means between said rod and release ring to move the rodupwardly, upon release or said ring, to maintain said anchoring meansinactive.

RUSSELL A. RANSOM.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,460,894 Dix July 3, 19232,188,409 Lane Jan. 30, 1940 2,200,172 Howard May 7, 1940

